- 兵之情主速乘人之不及由不虞之道攻其所不戒也
Opinions differ as to what Sun Tzŭ had in mind. Ts‘ao Kung thinks it is 其所恃之利 “some strategical advantage on which the enemy is depending.” Tu Mu says: 據我便地畧我田野利其糧道斯三者敵人之所愛惜倚恃者也 “The three things which an enemy is anxious to do, and on the accomplishment of which his success depends, are: (1) to capture our favourable positions; (2) to ravage our cultivated land; (3) to guard his own communications.” Our object then must be to thwart his plans in these three directions and thus render him helpless. [Cf. III. § 3.] But this exegesis unduly strains the meaning of 奪 and 愛, and I agree with Ch‘ên Hao, who says that 所愛 does not refer only to strategical advantages, but is any person or thing that may happen to be of importance to the enemy. By boldly seizing the initiative in this way, you at once throw the other side on the defensive.
19. Rapidity is the essence of war:
兵之情 means “the conditions of war,” not, as Capt. Calthrop says, “the spirit of the troops.” According to Tu Mu, 此統言兵之情狀 “this is a summary of leading principles in warfare,” and he adds: 此乃兵之深情將之至事也 “These are the profoundest truths of military science, and the chief business of the general.” The following anecdotes, told by Ho Shih, show the importance attached to speed by two of China’s greatest generals. In 227 A.D., 孟達 Mêng Ta, governor of 新城 Hsin-ch‘êng under the Wei Emperor Wên Ti, was meditating defection to the House of Shu, and had entered into correspondence with Chu-ko Liang, Prime Minister of that State. The Wei general Ssŭ-ma I was then military governor of 宛 Wan, and getting wind of Mêng Ta’s treachery, he at once set off with an army to anticipate his revolt, having previously cajoled him by a specious message of friendly import. Ssŭ-ma’s officers came to him and said: “If Mêng Ta has leagued himself with Wu and Shu, the matter should be thoroughly investigated before we make a move.” Ssŭ-ma I replied: “Mêng Ta is an unprincipled man, and we ought to go and punish him at once, while he is still wavering and before he has thrown off the mask.” Then, by a series of forced marches, he brought his army under the walls of Hsin-ch‘êng within the space of eight days. Now Mêng Ta had previously said in a letter to Chu-ko Liang: “Wan is 1200 li from here. When the news of my revolt reaches Ssŭ-ma I, he will at once inform his Imperial Master, but it will be a whole month before any steps can be taken, and by that
